Looking for some advice on replacing my gas tank. Developed a leak last fall and I've been driving it around making sure I don't fill over half way (at which point it will leak). I assume that it's leaking along a tank seam somewhere but can't get in there to view where it's leaking. Maybe it leaking from the fuel pump portal? - Is that common? Are seam leaks common?

In any case, I'm getting ready to order a new tank and I guess I should order a new fuel pump/ sender assembly too. Also thinking I'll need new tank straps as the ones on there now are original. Been looking at the horror show that is tank strap bolts ($35 per bolt - with one place quoting $42 to ship - so $112 for two bolts. LOL) but I'll figure out something there.

There are two holes in the top of the tank, I assume they're both for vents? Do both holes have the plastic vent things and can the old ones be reused or should they be replaced with new ones? Is there anything else I should have on hand in anticipation of swapping in a new tank?

Thanks for any advice.

 

I think it is more likely that a seal for the filler, vents, hose near tank, or pump port have failed than a seam. I imaging a big impact and dent could bust a seam. lacking a big impact, I think you have a leak in the aforementioned seals rather than the seam. The seam is unlikely to rust from inside, as almost always internal tank rust happens at the bottom of tank, as water sinks, gasoline floats, to rust happens at bottom where water maybe. The seam rarely fails. before buying new tank, check the other items carefully. I wager it is not the seam, not the tank itself. rather it is a seal fail, or hose fail at or near the tank from one of the numerous ports to the tank.

unless straps are damaged, Id not worry about reuse of them.

Gooly Id hate to buy a new tank and all the bits just to find a vent hose or filler hose is the culprit, and your tank is ok.

If you have a skid plate, pergaps remove it for better visability, and fill tank up a bit more till you see the leak, identify the source. you can gradually fill tank from a jerry can in your driveway rather than at a filling station, so that you can pour in a little at a time until leak is discovered. You can also use a mirror and flashlight to help see things, use the mirror and light to examine each port on sides and top of tank. Also you can shove a clean dry paper towel into the areas next to the hoses and ports that you cannnot see well, then fill tank, then remove the towels and see if any got gasoline soaked into them. You may need to drive a bit as sloshing of fuel maybe needed to cause leak for instance if the leak is from top of tank and it only leaks when gas is sloshed, but not leak when not sloshing. the paper towels will get wet as you drive as gasoline is sloshed onto the leak if their is a leak near the towel
gasoline can run from a top side seal leak, and run down to and along the seam such that you think it is the seam leaking.
Try some more diagnosis. I hope it is simply a torn filler or vent hose, or port seal that is the problem as that will be much less money to fix

lettuce know what you find!

ps.. if you end up needing a new tank, it would be prudent to replace the port fitting up top, as the plastic is already 30+ years old, and might be brittle and thus break or fail to reseal. of course cost might be a factor to consider, verses having to do it all over again if the old ones do leak.